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Seiji Ito - One of the best experts on this subject based on the ideXlab platform.
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Expression of hOvol2 in the XY body of human spermatocytes
Andrologia, 2016Co-Authors: H. Taniguchi, Ikuko Yao, Tayo Katano, Kazuhiko Nishida, Y. Morimoto, T. Matsuda, Seiji ItoAbstract:Summary Male infertility is common at infertile clinics, and 10–20% of infertile males are azoospermic. Non-obstructive azoospermia is a complex multifactorial disease, and the process of spermatogenesis remains largely unknown. Ovol1 and Ovol2, a family of zinc finger transcription factors, are expressed in spermatocytes at the Pachytene Stage and are suggested to be critical regulators of Pachytene progression in male germ cells. In this study, we examined the expression of human Ovol2 (hOvol2) in the seminiferous tubes of patients subjected to testicular sperm extraction. We first cloned hOvol1 and hOvol2 from the testis of one of the patients and found no alteration in these nucleotide sequences of this patient. While hOvol1 and hOvol2 were detected by RT-PCR in the testis of patients capable of spermatogenesis, they were not detected in those with Sertoli cell-only syndrome. We recently succeeded in preparing anti-Ovol2 antibody by immunising rats with recombinant mouse Ovol2 (mOvol2) and confirmed the specificity and cross-reactivity of this antibody with hOvol2 in cells transfected with hOvol1 or hOvol2 cDNA. hOvol2 expression was restricted to the XY body of spermatocytes at the Pachytene Stage. This study demonstrates that hOvol2 is expressed in germ cells and may be involved in spermatogenesis.
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restricted expression of ovol2 movo in xy body of mouse spermatocytes at the Pachytene Stage
Journal of Andrology, 2012Co-Authors: Ryusuke Chizaki, Ikuko Yao, Tayo Katano, Tadashi Matsuda, Seiji ItoAbstract:The development of multicellular organisms is controlled by sequential activation of a hierarchy of regulatory genes, which encode transcription factors having DNA-binding motifs. We previously identified a testis-specific zinc finger transcriptional factor, Ovol2/MOVO, as a mouse homologue of Drosophila Ovo. Because mice deficient in Ovol2/Movo die during early embryogenesis, its function in male germ cells has remained unknown. We have recently succeeded in preparing anti-Ovol2/MOVO antiserum for immunohistochemical use. In the present study, we demonstrated that Ovol2/MOVO protein started to be expressed in male germ cells at 2 weeks after birth and that Ovol2/MOVO expression was restricted to the XY body in spermatocytes at the Pachytene Stage. In a reporter assay, Ovol2/MOVO repressed the histone H1t promoter activity in the spermatogenic cell line GC-2spd. These results suggest that Ovol2/MOVO may play an important role in the XY body during spermatogenesis, possibly in the processes of XY body formation and meiotic sex chromosome inactivation.
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Restricted expression of Ovol2/MOVO in XY body of mouse spermatocytes at the Pachytene Stage.
Journal of andrology, 2011Co-Authors: Ryusuke Chizaki, Ikuko Yao, Tayo Katano, Tadashi Matsuda, Seiji ItoAbstract:The development of multicellular organisms is controlled by sequential activation of a hierarchy of regulatory genes, which encode transcription factors having DNA-binding motifs. We previously identified a testis-specific zinc finger transcriptional factor, Ovol2/MOVO, as a mouse homologue of Drosophila Ovo. Because mice deficient in Ovol2/Movo die during early embryogenesis, its function in male germ cells has remained unknown. We have recently succeeded in preparing anti-Ovol2/MOVO antiserum for immunohistochemical use. In the present study, we demonstrated that Ovol2/MOVO protein started to be expressed in male germ cells at 2 weeks after birth and that Ovol2/MOVO expression was restricted to the XY body in spermatocytes at the Pachytene Stage. In a reporter assay, Ovol2/MOVO repressed the histone H1t promoter activity in the spermatogenic cell line GC-2spd. These results suggest that Ovol2/MOVO may play an important role in the XY body during spermatogenesis, possibly in the processes of XY body formation and meiotic sex chromosome inactivation.
John R. Pehrson - One of the best experts on this subject based on the ideXlab platform.
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Histone macroH2A1.2 is concentrated in the XY-body by the early Pachytene Stage of spermatogenesis.
Experimental cell research, 2000Co-Authors: Sigrid Hoyer-fender, Carl Costanzi, John R. PehrsonAbstract:The pairing of sex chromosomes during meiosis in male mammals is associated with ongoing heterochromatinization and X inactivation. This process occurs in a specific area of the nucleus that can be discerned morphologically: the sex vesicle or XY-body. In contrast to X inactivation in the somatic cells of female mammals the reasons for X inactivation in the male germline remain obscure. We have recently demonstrated that the inactive X chromosome in somatic cells of female mammals is marked by a high concentration of histone macroH2A. Here we investigate X inactivation in the meiotic cells of the male germline. We demonstrate here that macroH2A1.2 is present in the nuclei of germ cells starting first with localization that is largely, if not exclusively, to the developing XY-body in early Pachytene spermatocytes. Our results suggest that inactivation of sex chromosomes in the male germ cell includes a major alteration of the nucleosomal structure.
Y. Rumpler - One of the best experts on this subject based on the ideXlab platform.
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Pattern of ribonucleic acid synthesis in human primary spermatocytes
Andrologia, 2009Co-Authors: C. Saussine, O. Gabriel-robez, Y. RumplerAbstract:RNA synthesis was studied autoradiographically using [3H]-uridine at different Stages of human spermatogenesis and especially at the Pachytene Stage. Morphological and functional evidence have shown the X Chromosome to be allocyclic relatively to the autosomes, and apparently inactive throughout the whole meiosis. No RNA precursor was incorporated by the X at any Stage of male meiosis. The authors suggest that this technique could be used in cases of human rearranged chromosomes, in order to elucidate the mechanism of spermatogenic breakdown in cases of hypofertility or sterility in humans.
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xy quadrivalent association and sterility in a man carrier of a reciprocal autosomal translocation involving the whole arm of an acrocentric chromosome t 2 15 q21 3 cen
Andrologia, 2009Co-Authors: W Yu, O Gabrielrobez, M F Croquette, Jeanmarc Rigot, Y. RumplerAbstract:Summary Meiotic and synaptonemal complex studies using electron microscopy were carried out on an infertile man with a 46,XY t(2q;15p). Synaptonemal complex analysis showed terminal asynapsis in the totality of quadrivalents and a high and significant frequency of association with the XY vesicle (80%), possibly related to the high amount of satellite DNA of the acrocentric chromosome 15. In this translocation carrier, the XY quadrivalent association at Pachytene Stage is positively correlated with the degree of spermatogenic breakdown after Pachytene Stage. Whether association with the non-paired segment represents the causative factor or only a secondary effect has still to be clarified.
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Meiotic study of hybrids in the genus Eulemur and taxonomic considerations.
American Journal of Primatology, 1997Co-Authors: R. Djelati, B. Brun, Y. RumplerAbstract:A reproductive study was conducted on seven hybrids of Eulemur showing chromosomal multivalents involving at least four chromosomes at the Pachytene Stage. Three individuals were infertile hybrids and one presented a reduced spermatogenesis. In three out of these four hybrids, multivalents were associated with the sex bivalent in a large number of spermatocytes (23%). The relative importance of the reduction of fertility in males linked to chromosomal multivalent formation as well as the genetic background is discussed with regard to the use of cytogenetic data for systematics. Our findings argue for the classification of Eulemur fulvus collaris and E. f. albocollaris in two separate species. In regard to their repartition area, their separation along a linear north-south axis in Madagascar is discussed.
Ryusuke Chizaki - One of the best experts on this subject based on the ideXlab platform.
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restricted expression of ovol2 movo in xy body of mouse spermatocytes at the Pachytene Stage
Journal of Andrology, 2012Co-Authors: Ryusuke Chizaki, Ikuko Yao, Tayo Katano, Tadashi Matsuda, Seiji ItoAbstract:The development of multicellular organisms is controlled by sequential activation of a hierarchy of regulatory genes, which encode transcription factors having DNA-binding motifs. We previously identified a testis-specific zinc finger transcriptional factor, Ovol2/MOVO, as a mouse homologue of Drosophila Ovo. Because mice deficient in Ovol2/Movo die during early embryogenesis, its function in male germ cells has remained unknown. We have recently succeeded in preparing anti-Ovol2/MOVO antiserum for immunohistochemical use. In the present study, we demonstrated that Ovol2/MOVO protein started to be expressed in male germ cells at 2 weeks after birth and that Ovol2/MOVO expression was restricted to the XY body in spermatocytes at the Pachytene Stage. In a reporter assay, Ovol2/MOVO repressed the histone H1t promoter activity in the spermatogenic cell line GC-2spd. These results suggest that Ovol2/MOVO may play an important role in the XY body during spermatogenesis, possibly in the processes of XY body formation and meiotic sex chromosome inactivation.
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Restricted expression of Ovol2/MOVO in XY body of mouse spermatocytes at the Pachytene Stage.
Journal of andrology, 2011Co-Authors: Ryusuke Chizaki, Ikuko Yao, Tayo Katano, Tadashi Matsuda, Seiji ItoAbstract:The development of multicellular organisms is controlled by sequential activation of a hierarchy of regulatory genes, which encode transcription factors having DNA-binding motifs. We previously identified a testis-specific zinc finger transcriptional factor, Ovol2/MOVO, as a mouse homologue of Drosophila Ovo. Because mice deficient in Ovol2/Movo die during early embryogenesis, its function in male germ cells has remained unknown. We have recently succeeded in preparing anti-Ovol2/MOVO antiserum for immunohistochemical use. In the present study, we demonstrated that Ovol2/MOVO protein started to be expressed in male germ cells at 2 weeks after birth and that Ovol2/MOVO expression was restricted to the XY body in spermatocytes at the Pachytene Stage. In a reporter assay, Ovol2/MOVO repressed the histone H1t promoter activity in the spermatogenic cell line GC-2spd. These results suggest that Ovol2/MOVO may play an important role in the XY body during spermatogenesis, possibly in the processes of XY body formation and meiotic sex chromosome inactivation.
Ikuko Yao - One of the best experts on this subject based on the ideXlab platform.
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Expression of hOvol2 in the XY body of human spermatocytes
Andrologia, 2016Co-Authors: H. Taniguchi, Ikuko Yao, Tayo Katano, Kazuhiko Nishida, Y. Morimoto, T. Matsuda, Seiji ItoAbstract:Summary Male infertility is common at infertile clinics, and 10–20% of infertile males are azoospermic. Non-obstructive azoospermia is a complex multifactorial disease, and the process of spermatogenesis remains largely unknown. Ovol1 and Ovol2, a family of zinc finger transcription factors, are expressed in spermatocytes at the Pachytene Stage and are suggested to be critical regulators of Pachytene progression in male germ cells. In this study, we examined the expression of human Ovol2 (hOvol2) in the seminiferous tubes of patients subjected to testicular sperm extraction. We first cloned hOvol1 and hOvol2 from the testis of one of the patients and found no alteration in these nucleotide sequences of this patient. While hOvol1 and hOvol2 were detected by RT-PCR in the testis of patients capable of spermatogenesis, they were not detected in those with Sertoli cell-only syndrome. We recently succeeded in preparing anti-Ovol2 antibody by immunising rats with recombinant mouse Ovol2 (mOvol2) and confirmed the specificity and cross-reactivity of this antibody with hOvol2 in cells transfected with hOvol1 or hOvol2 cDNA. hOvol2 expression was restricted to the XY body of spermatocytes at the Pachytene Stage. This study demonstrates that hOvol2 is expressed in germ cells and may be involved in spermatogenesis.
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restricted expression of ovol2 movo in xy body of mouse spermatocytes at the Pachytene Stage
Journal of Andrology, 2012Co-Authors: Ryusuke Chizaki, Ikuko Yao, Tayo Katano, Tadashi Matsuda, Seiji ItoAbstract:The development of multicellular organisms is controlled by sequential activation of a hierarchy of regulatory genes, which encode transcription factors having DNA-binding motifs. We previously identified a testis-specific zinc finger transcriptional factor, Ovol2/MOVO, as a mouse homologue of Drosophila Ovo. Because mice deficient in Ovol2/Movo die during early embryogenesis, its function in male germ cells has remained unknown. We have recently succeeded in preparing anti-Ovol2/MOVO antiserum for immunohistochemical use. In the present study, we demonstrated that Ovol2/MOVO protein started to be expressed in male germ cells at 2 weeks after birth and that Ovol2/MOVO expression was restricted to the XY body in spermatocytes at the Pachytene Stage. In a reporter assay, Ovol2/MOVO repressed the histone H1t promoter activity in the spermatogenic cell line GC-2spd. These results suggest that Ovol2/MOVO may play an important role in the XY body during spermatogenesis, possibly in the processes of XY body formation and meiotic sex chromosome inactivation.
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Restricted expression of Ovol2/MOVO in XY body of mouse spermatocytes at the Pachytene Stage.
Journal of andrology, 2011Co-Authors: Ryusuke Chizaki, Ikuko Yao, Tayo Katano, Tadashi Matsuda, Seiji ItoAbstract:The development of multicellular organisms is controlled by sequential activation of a hierarchy of regulatory genes, which encode transcription factors having DNA-binding motifs. We previously identified a testis-specific zinc finger transcriptional factor, Ovol2/MOVO, as a mouse homologue of Drosophila Ovo. Because mice deficient in Ovol2/Movo die during early embryogenesis, its function in male germ cells has remained unknown. We have recently succeeded in preparing anti-Ovol2/MOVO antiserum for immunohistochemical use. In the present study, we demonstrated that Ovol2/MOVO protein started to be expressed in male germ cells at 2 weeks after birth and that Ovol2/MOVO expression was restricted to the XY body in spermatocytes at the Pachytene Stage. In a reporter assay, Ovol2/MOVO repressed the histone H1t promoter activity in the spermatogenic cell line GC-2spd. These results suggest that Ovol2/MOVO may play an important role in the XY body during spermatogenesis, possibly in the processes of XY body formation and meiotic sex chromosome inactivation.
